In a known single-passenger inverted pendulum mobile vehicle, a pair of drive wheels are provided on a same axial line so as to be actuated individually by separate electric motors, and the vehicle is enabled to travel while standing upright under an inverted pendulum control process (See Japanese patent laid open publication No. 2006-131115, for instance)
Such a coaxial two-wheel vehicle can turn as required by causing a difference between the rotational speeds of the two wheels, and can even turn around a fixed yaw axis by rotating the two wheels in mutually opposite directions at a same rotational speed.
However, according to such a two-wheel vehicle, because the rider stands on a platform which is integral with the vehicle frame rotatably supporting the wheels, the rider moves jointly with the vehicle frame and therefore experiences a yaw acceleration as the vehicle makes a turn. Typically, such a vehicle is capable of turning very quickly, the rider may experience some discomfort owing to rapid changes in the direction of the movement of the vehicle. When the vehicle carries a cargo, owing to a strong centrifugal force that may be applied to the cargo, there is a danger of the cargo to fall off or to shift from a prescribed position on the vehicle frame.